: in control, assertive, presidential. whilebarackobamakepthis eyes and his energy low. >> it's very rare that stylistically there's such a clear triumph of one side over the other. >> reporter: a rally in denver, the president admitted he got surprised. >> when i got onto the stage, i met this very spirited fellow who claimed to be mitt romney. >> reporter: he charged romney changed his stance on taxes and spending. >> but if you want to be president, you owe the american people the truth. >> reporter: some felt mr. obama owed them a better debate. >> he looked like he was tired, drained. >> i think he didn't have the practice. >> you more worried obama might lose now? >> well, no, not really. >> reporter: obama strategists hint the boss learned a lesson. >> he'll review it and if he wants to make some changes in the next debate, he'll do so. >> reporter: romney strategists claim all that changed about their guy was the audience. >> i think people saw him for the first time, a lot of people, not in a 30-second attack ad or 12-second snippet on the news. but got to hear him directly. >> r